Combustion chamber in cylinder heads of internal combustion engines



Feb 27 1940 J. A. H. BARKEIJ GMBUSTION CHAMBER IN CYLINDER BEADS 0FINTERNAL COMBUSTIN` ENGINES Fiied uarcn 2, 193s 2 Sheets-Sheet 1Patented F eb. 27, 1940 COMBUSTION CHAMBER IN CYLINDER HEADS OF INTERNALCOMBUBTION ENGINES Jean A. H Barkeij, Altadena, Calif.

*Application March 2,

14 Claims.

The present invention is related to the subject matter of my previous'application No. 325,115 of December 10, 1928, now Patent No. 2,050,688,of August 11, 1936, and also related to the subject matter ofmyapplication No. 291,599 of July l0,

1928, and is a continuation in part of my application No. '721,721 ofApril 20, 1934.

This invention relates to the combustion chamber of a valve-in-headengine particularly. My object is to construct a restricted passagebetween the cylinder bore (or piston chamber) and the combustion chambercontaining the spark .ignition means, and to place in such aconstruction the spark ignition means closer to the edge ofthe'exhaustvalve than to the edge oi' the inlet valve. Said latterconstruction appears entirely satisfactory at any speed, because theturbulence created by said throat (mechanical turbulence) preventsmisflring at any speed and especially at low speeds. Said mechanicalturbulence prevents eifectively stagnation of gases in the neighborhoodof the spark ignition means.

Therefore,although the presentvinvention is particularly shown inrelation with a cylinder head having the valves in the head (thevalve-in-head type), it stands to reason that said principles may beapplied on any type of four-stroke cycle engine having exhaust and inletvalves or one exhaust valve and one inlet valve in a main explosionchamber communicating with said piston chamber orl cylinder bore throughsaid restricted passage between bore and the combustlon chamber,containing both of saidvalves.

I further place the spark ignition means in an auxiliary combustionchamber, having either a non-restricted passage or a restricted passagewith the main combustion chamber.

My rst object is to construct both valves, the

inlet and .exhaust valve inverted in the headY of the engine, and tolocate both valves substantially above the cylinder bore, so that themajor part of saidl valves, are located above the cylinder bore whenlooking'at said valves in top view towards said cylinder bore.

They both communicate either with the cylinder bore or piston chamberdirectly without any intermediate restricted passage i as shown in Figs.1 and 1A), or communicate with the piston chamber through anintermediate restricted passage therebetween.

This restricted passage is shown in Figs. 4 and 5, and may be formed aspreferrrd provided it causes a mechanical turbulence of the charge inthe main combustion chamber and in the auxiliary chamber at the end ofthe compression 1938, Serial No. 198,550

period (and apart. of course, from the restricted passage which may beconstructed between the said main chamber and auxiliary chamber), ac-`celerating thereby the burningA of the charge and insuring tiringthereof by the spark plug wheresoever yit may be placed in such a -combustion chamber. l As shown in Fig. 4 the undersurface of the cylinderhead may form the entire restricted passage, but the area of thisrestricted passage should be liberal and substantially greater than thearea or inlet capacity of the inlet valve above it, so that the freshgases are not obstructed when streaming from the inlet valve towards thepiston chamber I andpast this restricted passage. It is, however,understood that this restricted passage between the main combustionchamber and the piston chamber. may be formed either entirely by thecylinder head, or partly by the cylinder head and partly bythe cylinderbore. It may lie further entirely over the cylinder bore or at one sidethereof.

My second object is to construct the main combustion chamber directlybelow the valves, and to construct adjacent thereto a second, smaller,explosion chamber or bay adjacent to the main explosion chamber, thesetwo chambers being separated by a passage, which may or may not berestricted. In my Patent No. 2,050,688 0i' Au#- gust 11, 1936, has beenclaimed the variety shown in Figs. 1 to 5 showing a combustion chamber,or chambers, without valves, the valves being placed outside saidchambers or chamber.

The volume of said additional chamber should not be greater than about aquarter of the main chamber but can be made much smaller of course. Thisauxiliary chamber' may have any shape, but the gases ignited in saidchamber must ignite first the gas mass in the neighborhood of theexhaust valve.

My third lobject is to provide the larger combustion chamber with aspark plug in substantially horizontal position, and likewise the sparkplug in the smaller explosion chamber.

My fourth object is to place both. of said spark plugs approximately ina plane perpendicular to the piston pin, said plane passing through theaxis of the exhaust valve approximately.

My fth object is to have simultaneous ignition from both spark plugs, ifthey are -both applied on this combustion chamber. In other words asingle spark plug may be used and mounted in either one of saidchambers, in whichlatter case these form practically one chamber.

My sixth object is to raise the compression ratio'inV said engine by thelocation of said single or double spark plugs in certain positionscloser to the exhaust valve than to the inlet valve for reasons to beexplained hereinafter.

These various objects are shown in various combinations in the followingdrawings, but they all contain the feature of the first and sixthobject.

Referring to the drawings, Fig. 1 is a vertical section of a cylinderand cylinder head on the section lines I-I of Fig. 1A, and show theapplication of two spark plugs firing simultaneously.

Fig. 1A is a horizontal section of the cylinder head on the section lineiA-IA of Fig. 1. Figs. 2 to 5 are similar vertical sections showing onlya single spark plug.

The cylinder is, of course, only one of a multicylinder-engine. In saidfigures the numeral l designates the cylinder head, 2 the cylinder, andla, 2a are respectively the water jackets thereof. Numeral l designatesthe piston, I the piston pin, l the connecting rod. 8 is the mainexplosion chamber having the greater volume, 'I the smaller chamber.Numeral i designates the spark plug in'the smaller chamber, 8 that inthe larger chamber. Numeral I designates the exhaust valve, Illa theexhaust passage, il is the inlet valve, Ila the inlet passage. Howeverif a single chamber is shown, either spark plug may be designated by thenumeral 8 or 9.

The combustion chamber 6 is shown here as communicating unrestrictedlywith the piston chamber 3a, but there may be such a restriction if amechanical turbulence is desired to be caused in the main chamber i, bythe piston approaching said restriction when reaching its top deadcenter position. The type with the restricted passage is shown in Figs.4 and 5 on the second sheet.

'I'his restricted passage should be carefully discernedA from anotherrestricted passage la which may be formed between the main combustionchamber 6 and the additional combustion chamber l. In Fig. 1 there is nosuch restriction, because the circular form of the main combustionchamber 6 goes over into the angular chamber 'l without forming anyrestriction at all so that they form virtually one chamber. .This formof Fig. l is very distinct from the type shown in Fig. 5 in which thevchamber l is positively separatedfrom the main chamber 6 by arestricted passage, which has to perform a double and definite functionseparate from the 'other features to be discussed hereinafter at the endof the specification.

In the present construction the valves can open and close at any desiredtime, since the distance between valves and top of piston when on topdead center position is sufficient to allow any liberal lift of saidvalves downwardly. This feature is retained in all types andmodifications, and is closely connected with the feature to retain thecapacity of both valves to inhale and exhalerespectively fresh andburned gases.

Another feature of extreme importance is the position of the spark plug.Spark plug 8 is offset in chamber 1 and so is,spark plug 9 in chamber 6from a transverse plane midway the axes of said valves. If only a mainchamber 6 is used containing both valves, the spark plug 9 being locatedin the neighborhood of the exhaust valve, the gas in this neighborhoodbegins to burn first and compresses the unburned portion of the gastowards the cooler regions of said chamber. The exhaust valve is by farthe hottest part in the explosion chamber and the heat radiating there-,of the cylinder.

from causes detonation of the unburned portion of the gas when theignition flame is initiated in the neighborhood of the inlet valve, orat a pointremote from the exhaust valve in said chamber.

Equally when spark plug 8 alone is used and when placed as shown in Fig.1A, the gas in the neighborhood of the exhaust valve is burned first andduring a certain stadium of the combustion a portion of the gas iscrowded towards the cooler regions of the combustion chamber.

When both spark plugs are fired simultaneously at least one of themshould be placed as shown in Fig. 1A, but preferably both of them, asshown.

, In the latter case, the action of the ignition flame from chamber l issomewhat undone, as the flame therefrom will compress not only anunburned portion of gas in chamberj but also a burned or burning portionof gas ignited by spark plug 9. Both plugs will do the same thing, crowdthe unburned portion towards valve Il, and always away from the exhaustvalve.

Therefore the latter construction with two spark plugs is only preferredfor very fast motors and where fuel economy is of first importance, likein truck engines, and in aeroplane engines.

I do not intend therefore to restrict myself to the construction of bothplugs ilring simultaneously, but consider the scope of this applicationto lie about in the scope of the following claims, including the use ofa single spark plug in certain positiions.

'Ihe position of the spark plug 9 or that of 8, or both, is thereforedependent on the position of the exhaust valve, but the position of thisexhaust valve may be anywhere, except in the center of the combustionchamber, opening downwardly as shown. The form of the combustion chamberchanging according to the relative position of the valves is thereforealso secondary, as the form thereof depends largely upon the relativeposition of the valves that is in upright or downward position. Thefeature of the double chamber is therefore also unimportant for so faras concerns theposition of the spark plug near the exhaust valve, and inthe same plane therewith a single chamber may be used if only spark plug9 is used, or if only spark plug 8 is used, diametrically opposite theposition of spark plug 9. Even if both spark plugs are firedsimultaneously, they may be placed in a single chamber. with 0r Withoutthe restricted passage, but both of them are by preference substantiallyin the same transverse plane with the axis of the exhaust valve, if thevalves in the engine are placed in a single plane lengthwise the engine.

The mechanism to lift the valves is not shown in the drawings, but theseusual pushrods are supposed to be either to the right or to the left Ifthe pushrods are on one side, the exhaust and inlet manifold are usuallyat the other side.

It is finally preferred to construct the sepmethod of igniting afuel-air mixture in an internal combustion engine of the explosive type.rifhe chamber may have practically any form, it may be a double or asingle chamber with or without a restricted passage therebetween. The

location of the single or double spark plugs alheat from the yexhaustvalve into said mixture,

especially in the neighborhood of the -exhaust valve and especially ofits very center this being Vthe hottest part in the combustion chamber.

Assuming that these temperatures remain the same with any position ofthe spark plug(s). it remains a fact that during the ignition, theexhaust valve continues to radiate heat. When the pressure rises due toa part of the fresh gases already burned after an initial ignition bythe spark plug near the exhaust valve, and when the unburned part iscrowded by the burned part towards the inlet valve, the inlet valve willnot radiate heat into said unburned part and therefore will not causedetonation in said unburned part because the heat of the inlet valvewill not be sufficient to cause detonation thereof.

Conversely if the unburned part (raised in temperature by the pressureof the burned part initially ignited near the inlet valve) is crowdedtowards the exhaust valve, the radiation of heat by said exhaust valveinto the said unburned part will cause detonation in said unburned parteven when the temperature and pressure of said gases in the neighborhoodof the exhaust valve were the same as those near the inlet valve. Duringthe entire compression period. however, the gases in theneighborhood o fthe exhaust valve are inuenced by the heat of the exhaust valve,notwithstanding the fact that the fresh charge remains more or less in astate of turbulence, especially if a restricted passage is appliedbetween combustion chamber and piston chamber (a socalled Ricardo head,here for valve-inf-head structures.) 1

If detonation begins to occurin the neighborhood of the exhaust valve(the gas being ignited near the inlet valvel, a vicious circle starts,as the exhaust valve gets hotter and hotter by said detonation, and thiscauses heat losses and a decrease in thermal efficiency. When ignitingthe charge initially in the neighborhood of the exhaust valve, thisvicious circle cannot start, heat losses are less. thermal eiciencyhigher. Therefore the position of the spark plug is of profoundimportance and significance.

As has been stated hereinbefore that the valves maybe placed anywhereand the form of the combustion chamber may be valmost any shape, hasonly one restriction. The exhaust valve should not be placed in thecenter of the combustion chamber, because if the single spark plug isplaced close to it, the ame will propagate in all directions towards allcorners of the chamber and it would not be possible to crowd the unburntportion of the gas, compressed by the pressure of the burnt portion ofthe gas before detonation may occur, towards the cooler portion of thechamber where the other valve is located. If the exhaust valve is placedmore or less lin a corner and the ignition is started there, it standsto reason that all of the gas in the neighborhood oi the exhaust valvecan be burned rst and the pressure created thereby can crowd theunburned portion away from the exhaust valve' region and towards theremaining part of this chamber containing the inlet valve. It furthervstands toreason that it is totally unimportant where or whether theinlet valve is placed in the main chamber or not, provided the singlespark plug is placed closer to the exhaust valve than to the inletvalve. The gas must be initially ignited in the neighborhood of theexhaust valve and preferably in an auxiliary chamber in such a way thatthe flame darting from the spark plug in said auxiliary chamber reachesfirst the neighborhood of the exhaust valve and burns ilrst the chargeadjacent to thel exhaust valve.

It is further' an important feature that the inlet and exhaust valve orvalves are so located that the reciprocating piston never can touchthem. This is an important feature in any type of internal combustionengine, the high compression type especially, because if the compressionspace is very small the'valves can move entirely -free from the pistonand never can be touched by them, even if they did not close in time.

In Figs. 2 to 5 I have shown the two types discussed, the one with arestricted passage between the combustion chamber 8 and the pistonchamber. 3a,- and the other without such a restricted passage, but allusing only a single sparkplug closer to the edge or centerof the exhaustvalve than to the edge or center of the inlet valve. The position inhorizontal cross section of the sparkplugs in Figs. 2 and 5 are similarto the kcorresponding positions of sparkplugs 8 and 9 in F18. 1A.

Fig. 2 shows the said second type and the sparkplug 8 as shown in Fig.1A.

Fig. 3 shows the same type, showing the sparkplug 8 as shown in Fig'.1A.

Fig. l having substantially no restricted passage between the mainchamber 6 and the additional chamber 1, and the type shown inFig. 5 inwhich there is such Va. substantial restriction between these twochambers.

On the compression stroke in the type of Fig. 5, the mixture is forcedinto the chamber 1, through the restricted passage la, with greaterspeed and causing therein a greater turbulence before the spark ignitesthe mixture therein, than in the type of Fig. l or Fig. 3. Therefore wemay expect in the first type, also on account of such a kind of Venturipassage, that the burned gases will stream from said chamber 1 into thechamber 6 with greater speed than in the case of Fig. 1.

I may employ either one of said constructions in either one o f thecombustion .chambers discussed, the one having a restricted passagebetween the cylinder bore and the combustion' gases streaming therefromupon ignition reach the neighborhood of the exhaust valve rst.

I may construct such passages la', and chambers 1, in varying form,increasing or decreasing the area of said passage relative to the volumeof the additional chamber 1, and I may vary the volume of the chamber 'Irelative to the volume of chamber 6. By narrowing such a passage Iincrease the speed with which the fresh mixture enters this chamber 1and likewise I increase 'the speed with which the burned gases streamtherefrom into chamber i, to suit different engines and differentconditions.

Various modifications are obvious and fall under the scope of thefollowing claims.`

I claim:

1. In a four stroke cycle internal combustion engine of the explosivetype, a cylinder with a cylinder bore, a cylinder head1, an explosionchamber in said cylinder head communicating with said cylinder bore, aninlet valve and an exhaust valve-in said explosionchamber, an

additional explosion chamber of relatively smallvolume compared withsaid main explosion chamber and communicating restrictedly with saidmain explosion chamber, a sparkplug in said additional chamber at theperiphery of said combustion chamber and located closer to the edge ofthe exhaust valve than to the edge o1' said inlet valve, said additionalexplosion chamber being otherwise permanently closed, said inlet valveadmitting all the gas to be burned to said main combustion chamber, andanother sparkplug substantially diametrically opposite said firstsparkplug across the cylinder bore and means to ignite said sparkplugssubstantially simultaneously.

2. The combination of claim 1, in which said sparkplug and additionalchamber are so located that the burned gases streaming from said latterchamber reach the edge of said exhaust valve before reaching the edge ofsaid inlet valve in said, main explosion chamber.

3. In a four stroke cycle internal combustion engine of the explosivetype, a cylinder with a cylinder bore, a cylinder head, a main explosionchamber in said cylinder head communicating restrictedly with saidcylinder bore, an inlet and an exhaust valve in said main chamber, anadditional explosion chamber of relatively small volume compared withsaid main chamber, cornmunicating with said main chamber through apassage, said latter chamber being otherwise permanently closed, asparkplug in said additional explosion chamber located substantiallycloser to the edge of said exhaust valve than to the edge of said inletvalve in said main chamber, said inlet valve admitting all the gas to beburned to said main combustion chamber, and another sparkplug on theother side of said cylinder bore similarly situated and means to firesaid sparkplugs substantially simultaneously.

4. The combination of claim 3, in which a. second sparkplug is placed insaid main chamber also located substantially closer to the edge of saidexhaust valve than to the edge of said inlet valve in said main chamber.

5. In a four stroke internal combustion engine of the explosive type, acylinder with a cylinder bore, a piston therein, a cylinder head closingsaid. bore, a main combustion chamber in said head communicating withsaid cylinder bore through a restricted passage therebetween, an exhaustvalve and an inlet valve in said chamber opening substantiallydownwardly into said chamber towards said piston, two sparkplugs in saidchamber both located substantially further ber than from the center ofsaid exhaust valve and both substantially farther away from the edge ofinlet valve than from the edge of said. exhaust valve and the center ofsaid exhaust valve being substantially removed from the center of saidcombustion chamber and said sparkplug being removed substantially fromthe center of said combustion chamber.

6. The combination of claim 5, in which one of said sparkplugs is placedfurther in an odset, additional chamber, communicating with said mainchamber restrictedly.

7. In an internal combustion engine of the four-stroke cyclevalve-in-head type, a cylinder, a piston reciprocating therein, acylinder head having a main combustion chamber communicatingrestrictedly with the piston chamber in said cylinder through arestricted passage overlying the cylinder bore at one side thereof,inverted intake and exhaust valves opening downwardly in said chamber,asingle sparkplug in said combustion chamber located substantiallycloser to the center of said exhaust valve than to the center of saidcombustion chamber, and located at the same time in an ignition baylocated at the periphery of said main combustion chamber.

8. In an internal combustion engine of the four-stroke cyclevalve-in-head type, a cylinder, a piston reciprocating therein, acylinder head having a main combustion chamber communieatingrestrictedly with the piston chamber in said cylinder, an intake valveand an exhaust valve in said cylinder head opening downwardly into saidcombustion chamber toward said piston, and the restricted communicationhaving a passage substantially greater than the area of said inletvalve, an additional explosion chamber of relatively small volumecompared with said main chamber, having a single sparkplug in saidadditional chamber, and located closer to the center of said exhaustvalve than to the center of said combustion chamber, and located furthercloser to the center of said exhaust valve than to the center of saidinlet valve, said additional chamber located at the outer edge of saidmain combustion chamber.

9. In a four-stroke cycle internal combustion engine of thevalve-in-head type, a cylinder with a cylinder bore, a cylinder headclosing said bore, a main explosion chamber in said head communieatingrestrictedly with said cylinder bore, an exhaust valve and an inletvalve in said main chamber in inverted position opening downwardly intosaid chamber, said restricted communication having an area exceeding theinlet area of said inlet valve, an ignition bay communicatingrestrictedly with said main chamber and a single sparkplug located atthe inside edge of said ignition bay and at the same time closer to theedge of said exhaust valve than to the edge of said inlet valve. l

10. In afour-stroke cycle internal combustion engine of the explosivetype, a cylinder with a cylinder bore, a piston therein, a cylinder headclosing said bore, a main combustion chamber in said head communicatingwith said cylinder bore through a restricted passage therebetween whichoverlies the cylinder bore at one side thereof, an exhaust valve and aninlet valve in said chamber opening substantially downwardly into saidchamber towards said piston, a single sparkplug in a small auxiliarychamber communicating with said main chamber, the exit of saidauxlliarychamber located substantially further away from the center of saidexplosion chamber than from the center of said exhaust valve and thecenter of said exhaust valve being substantially removed from the centerof said combustion chamber.

il. The combination of claim 10 in which said auxiliary chambercommunicates unrestrictedly with said main chamber.

12. The combination oi claim 10 in which said auxiliary chamber orignition bay communicates substantially restrictedly with said mainchamber.

13. In a four-stroke cycle internal combustion engine of the explosivetype and of the valve-inhead type, a cylinder with a cylinder bore, acylinder head closing said bore, a main explosion chamber in said headcommunicating restrictedly with said cylinder bore, an exhaust valve andan inlet .valve in inverted position in said main chamber, an ignitionbay located at one side of said main chamber and having a volumesubstantially smaller than that oi said main chamber, not exceeding 25percent thereof, said ignition bay having an exit located substantiallyon that side of said main chamber where said exhaust valve is located, asingle sparkplug in said ignition bay so that the ame starting therefromupon ignition does not hit directly the exhaust valve but bums ilrst themixture in the neighborhood of said exhaust valve and subsequently thatin the neighborhood ot said inlet valve. said ignition bay communicatingrestrictedly with said main chamber and said single sparkplug beingcombustion chamber in said head communicating restrictedly with saidcylinder bore, valve controlled exhaust and inlet ports communicatingwith said main combustion chamber, an auxillary combustion chambercommunicating restrictedly with said main chamber above said restrictedpassage, and having a volume'substantially smaller than that of saidmain chamber and. not exceeding one third of the total volume of thecompression space thereof. and afsingl'e sparkplug in said auxiliarychamber ,and another sparkplug in said main chamber.

J. A. H. BARKEIJ.

DISCLAIMER 2,191,746.Jean- A. H.' Barkej, Altadena, Calif. CouBUsnoNCHAMBER 1N CYLIN- DER HEADS or INTERNAL CoMBUszrloN ENGINES. Patentdated Feb. 27, 1940. Disclaimer filed Nov. 15, 1946, by the inventor.Hereby enters disclaimer -to claim 4 and to the subject matter containedin lines 44 to 53 inclusive, second column, page I.

[Qc'ial Gazette December 10, 1946.]

Certificate of Correction Patent No. 2,191,746.

February 27, 1940.

. a JEAN A. H. BARKEIJ A It is hereby certied that error ap ears in theabove numbered patent requiring correction as follows: In' the dra Fig.5 should appear as shown below instead oi as in the patent? griffig/r fFIG. 5 and that the said Letters Patent should be read with thiscorrection there same may conform tothe record of the case in the PatentOlice.

in that the Signed and sealed this 4th day of March, A. D. 1947.

LESLIE FRAZER,

First Assistant Uommz'ssoner of Patents.

DISCLAIMER 2,191,746.-Jean A. H. Barkeij, Altadena, Calif. CoMBUs'rioNCHAMBERS 1N CYLINDER 'HEADS or INTERNAL CoMBUs'rIoN ENGINES. Patentdated Feb. 27, 1940. Disclaimer filed Mar. 24, 1947, by thc inventor.

Hereb enters disclaimer whereby the scope of the disclaimed fourth, andfifth object, an claim 4, is emphatically applied, i. c. eliminated fromthe entire patent or specification, drawings, description and claims.

Therefore the fifth ob'eet, i. e. simultaneous firing has been alreadyeliminated by the first disclaimer of ov. 15, 1946, from the explanatoryor descriptive matter in lines 27 to 32 on page 2, column 2, and fromthe lines 50 to 56 in the same column, and therefore also from theclaims.

Therefore the fourth object, i. c. two sparkplugs closer to the edge ofthc exhaust valve than to the edge of the inlet valve, has been alreadydisclaimed by the first disclaimer of Nov. 15, 1946, from the scope ofthe-claims with two sparkplugs.

The condenser in Fig. 1a is disclaimed.

[Oficial Gazette May 20, 1.947.]

Disclaimer 2,191,746.Jean A. H. Barkeij, Altadena, Calif. ConBUs'rxoNCullmann IN CYLIN- DEB HEADS or INTERNAL CouBUs'rxoN ENGINES. Patentdated Feb. 27, 1940. Disclaimer led Feb." 26, 1948, by the inventor.

Hereby enters disclaimer to pgs 2, column l, -9 inthe larger chamber,lines 24-25, page 2, column 1, 1n es 66-67, to -in chamber 6-, in line 4same column to various objects are shown in various, and to -butthey^al1 in lines 5-6 same column. l Y

Hereby limits the scopeof claims 1, 2, 3 to non-simultaneous firing inview of the prior disclaimers and in view of description in lines 28 to33, page 2, column 2, and further limits the interval ofnon-simultaneous firing to the range of 2 to 12 cllgankshgft rotation,and preferably to the approximate center thereof which is a out 6 y Andfurther limits the scope of claim 1 for so far as concerns the positionof the second sparkplug, to a position closer to the edge of the inletvalve than to the edge of the exhaust valve on account'of thediametncally opposite osition of the second sllarkplug with respect tothe first sparkplug, which is closerto t e edge of the exhaust v ve.

And further limits the scope of claim 3 for so far as concerns thesecond sparkplug to a osition closer to the ed e of the inlet valve thanto the edge of the exhaust valve, and imits the Wordssimarlysituated-solely to a position yin another auxiliary chambercommunicating with the main chamber as shown in Fig. 1a, and not to aposition also closer to the edge of the exhaust valve thaxl'to the edgeof the inlet valve, as was claimed and subsequently disclaimed in claim4, which limited claim 3 to such a osition only and originally.

And urther limits the sequence of the non-simultaneous to the sequencedescribed in the description, in which the ignition isfinitiated in t ehottest part of the chamber, where the exhaust valve is located.

(Oficial Game April 2Q, 194s.)

Certificate of Correction February 27, 1940.

Patent No. 2,191,746.

JEAN A. `H. BARKEIJ It is hereby certified that error appears in theabove numbered patent requiring correction as follows: In the drawing,Sheet 2, Figure 4 should appear as shown vbelow instead of as 1n thepatentrs Patent should be read with this correction therein that the andthat the said Lette same may conform to the record of the case in thePatent Ofiice.

Signed and sealed this 29th day of June, A. D. 1948;

THOMAS F. MURPHY,

Assistmtt Oommzssoner of Patents.

